Seal for a rotary piston device

ABSTRACT

A rotary piston engine, motor or pump having a rotor eccentrically mounted on a shaft and positioned within a housing to define a number of chambers, the rotor having a number of lobes equal to one less than the number of chambers and being rotated counter to the direction of rotation of the shaft to volumetrically displace a fluid in said chambers. A number of idler rollers are mounted in the housing at the points of intersection of the chambers in a position to engage the outer periphery of the rotor and to seal the chambers in the housing from each other. Vanes or brushes are provided in the housing to seal the outer surface of the idler rollers.

United States Patent Link SEAL FOR A ROTARY PISTON DEVICE Edwin A. Link,317 S. Greenfield Ave., Waukesha, Wis. 53186 Filed: Mar. 18, 1974 Appl.N0.: 452,214

Inventor:

US. Cl. 415/125; 418/61 B Int. Cl F04c 27/00; FOlc 19/00 Field of Search418/104, 125, 127, 128, 418/129, 61 B; 123/845 References Cited UNITEDSTATES PATENTS Primary Examiner-C. J. Husar Assistant ExaminerLouis J.Casaregola Attorney, Agent, or FirmRona1d E. Barry [57] ABSTRACT Arotary piston engine, motor or pump having a rotor eccentrically mountedon a shaft and positioned within a housing to define a number ofchambers, the rotor having a number of lobes equal to one less than thenumber of chambers and being rotated counter to the direction ofrotation of the shaft to volumetrically displace a fluid in saidchambers. A number of idler rollers are mounted in the housing at thepoints of intersection of the chambers in a position to engage the outerperiphery of the rotor and to seal the chambers in the housing from eachother. Vanes or brushes are provided in the housing to seal the outersurface of the idler rollers.

8 Claims, 4 Drawing Figures US. Patent Nov. 4, 1975 Sheet 1 of23,917,437

2o, n "A? 32/16 14 25 Q Q R I 546/40 3+Lfl2 US. Patent Nov. 4, 1975Sheet 2 of2 3,917,437

SEAL FOR A ROTARY PISTON DEVICE BACKGROUND OF THE INVENTION The presentinvention is an improvement on my earlier US. Pat. No. 3,340,855, issuedon Sept. 12, 1967 and entitled Rotary Piston Engine. In my previouspatent the engine was provided with a seal between flexible sections inthe walls of the housing and the periphery of the rotor, the seal beingbiased by increasing the pressure in the space behind the flexiblesections of the walls.

SUMMARY OF THE INVENTION The rotary engine of the present invention isprovided with an improved seal between the rotor and the housing thathas a longer life and can be more easily replaced. This seal is formedbetween removable idler rollers positioned in openings in the housingand the rotor. Each idler rotor is positioned to ride on the surface ofthe rotor and is sealed on the surface of the idler rollers. The brushesor vanes can be easily replaced whenever the seal becomes wom. A morepositive seal is provided by intermeshing gear teeth located on theidler roller and on the surface of the rotor.

DRAWINGS FIG. 1 is a side view in section of a rotary piston engineshowing the improved seal assembly of the invention;

FIG. 2 is a cross sectional view of the engine showing the flow paththrough the drive shaft;

FIG. 3 is a side view in section of a pump showing the seal assembly ofthe invention; and

FIG. 4 is a cross sectional view of the fluid flow path through thedrive shaft.

DESCRIPTION OF THE INVENTION chambers from each other. These sealassembliesS provide a positive seal between the rotor and the housingwhich are subject to little or no wear but can be readily replaced, ifnecessary.

The Rotary Piston Engine (FIGS. 1 and 2) The rotary piston enginegenerally includes a stator or housing 12 and a rotor 14 mounted forrotation on a hub 16 which is eccentrically located on the shaft 17. Inan engine of this type the hub 16 and shaft 17 rotate in acounterclockwise direction and the rotor 14 rotates in a clockwisedirection. The motion of the rotor 14 within the housing 12 willvolumetrically displace any gases in the chambers of the housingproducing compression, expansion, exhaust and intake strokes withrespect to each of the chambers.

The housing 12 includes a central chamber 18 and a pair of side plates20 secured to each side of the member 18 by bolts 22. A number ofchambers 24 are formed within the housing 12 between arcuate wallsurfaces 26 provided in the member 18 and the inner wall surface 21 ofthe plates 20. Five chambers 24 are contemplated herein. However, thenumber of chambers can be varied depending on the number of rotor lobesas described hereinafter. A threaded opening 28 is provided through thewall of the member 18 into each of the chambers 24. A circular recess 32is provided at the intersection of the arc uate wall surface 26 betweeneach of the chambers 24. A pair of slots 34 are angularly disposed inthe arcuate surface 32 with their axes intersecting at the center of thecircle of revolution of the surface 32.

The drive shaft 17 is journalled in openings 38 in the walls 20 in acoaxial relation to the axis of the housing member 18 with the hub 16located between the walls 20. The shaft 17 is provided with an inletbore 40 at one end and an outlet or exhaust bore 41 at the other end.

The hub 16 is mounted on the shaft 17 to rotate eccentrically withrespect to the shaft and is provided with a first or inlet passage 42and a second or exhaust passage 44. The inlet passage 42 communicateswith the chambers 24 through a slot 46. The passage 44 communicates withthe chambers 24 through a slot 48. The peripheral length of the slots 46and 48 are determined by length of time required for opening and closingof the passages 42 and 44, respectively.

The rotor 14 is symmetrical and includes four lobes 50. The peripheralsurface 52 of each of the lobes 50 has a radius of curvature slightlysmaller than the radius of curvature of the peripheral surface 26 of thechambers 24. An exhaust port 54 and an inlet port 56 are provided in twoof the diametrically opposite lobes 50 of the rotor 14. The exhaustports 54 are axially located in a position to communicate with the slots48 in the hub 16 The inlet ports 56 are coaxially located in position 40communicate with the slot 6 in the hub 16. The rotor 14 is mounted forrotation on the hub 16 and is rotated in the opposite direction to thedirection of rotation of the shaft 17. The slots 46 and 48 are axiallyarranged on diametrically opposite ends of the hub 16 to open an inletport 56 and an exhaust port 54 simultaneously. The length of time thatthe inlet port 56 and exhaust port 54 are opened will depend on theperipheral length of the slots 46 and 48, respectively.

Ignition of the combustible mixture in the chambers 24 is achieved bymeans of spark plugs 60 provided in the threaded openings 28 in themember 18. The spark plugs are timed to ignite the combustible mixturein a time sequence 1, 3, 5, 2, 4 as noted on FIG. 1 of the drawings.

Seal Assemblies 5 In accordance with the invention, the chambers 24 aresealed from each other by means of a number of seal assemblies 5. Asseen in FIG. 1, five seal assemblies are provided in the housing todefine five chambers or cavities 24 in the housing. Each seal assembly 5in cludes an idler roller 62 mounted for rotation in the arcuate opening32 in the member 18. Each of the idler rollers 62 is mounted forrotation on a pin 64 in a position to sealingly engage the outerperipheral surfaces 52 of the lobes 50.

The chambers 24 are sealed by means of intermeshing gear teeth 66 and 68provided respectively on the peripheral surface 52 of the rotor and thesurface of the idler rollers 62. In this regard the gear teeth 66 areprovided on the outer surface of the lobes 50 to form a 3 continuoussea] surface. A corresponding gear tooth arrangement is provided by thegear teeth 68 on the outer periphery of the idler rollers 62. The rotor14 is designed so that the teeth 66 on the rotor will continuouslyintermesh with the teeth 68 on each of the idler rollers 62.

Means are provided for sealing the spaces between the rotors 62 and thearcuate surfaces 32 in the member 18. Such means is in the form of anumber of brushes or vanes 72 positioned in the recesses 34 in themember 18. Two brushes 72 are provided foreach idler roller 62. Thebrushes are biased into engagement with the surface of the gear teeth 68on the rollers 62 by means of light springs 74 located at the inner endsof the bores 34. The brushes 72 are subject to wear as a result of thefrictional engagement of the brushes with the ends of the gear teeth 68but can be easily replaced by merely removing the idler rollers 62.

The Pump (FIGS. 3 and 4) The pump 80 is substantially identical to theengine in that the pump includes a stator or housing 82 and a rotor 84which is mounted for rotation on a hub 86 eccentrically located on ashaft 87. The pump operates in the same manner as the engine 10 in thatthe rotor 84 rotates in a clockwise direction and the shaft 87 rotatesin a counterclockwise direction producing a planetary motion between theshaft, rotor and housing. The motion of the rotor 84 within the housing82 will volumetrically displace any fluid in the chambers in the housingas a result of the compression and expansion of the chambers.

The housing 82 is identical to the housing 12 for the engine andidentical numbers have been used for the pump where the same parts havebeen previously identified in the engine.

The drive shaft 87 is provided with an inlet bore 90 at one end and anoutlet or exhaust bore 91 at the other end. The hub 86 is eccentricallymounted on the shaft 87 and is provided with a first or inlet passage 92and a second or exhaust passage 94. The inlet passage 92 communicateswith the chambers 24 in the housing through slots 96 and the exhaustpassage 94 communicates with the chambers 24 through slots 98.

The rotor 84 is symmetrical and is identical with the rotor 14 andidentical numbers have been used where the rotors are identical. In thisregard, it should be noted that the rotor 84 is provided with ports 100between each of the lobes 50. Ports 100 act as both inlet and exhaustports depending on the position of the slots 96 and 98 in the hub 86.Referring to FIG. 3, it should be' noted that two of the ports 100 areconnected to the slots 96 and the other two ports 100 are connected tothe slot 98. The two ports 100 connected to the slot 96 providecommunication with the inlet bore 90 in the shaft 87 and the two ports100 communicate with the slot 98 providing fluid communication with thedischarge passage 91 in the shaft 87.

In a pump the shaft 87 will be driven counterclockwise as seen in FIG. 1producing expansion and compression strokes in the chambers 24. Fluidwill be drawn into the chambers 24 on the expansion strokes through theslot 96 and will be volumetrically displaced from the chambers 24through the slot 98.

The seal assemblies 5, as seen in FIG. 3, are identical to the sealassemblies described for the engine in FIG. 1. Identical numbers havebeen used for identical parts.

The function of the seal assemblies is substantially the same asdescribed above in that the idler rollers 62 sealingly engage theperipheral surface of the rotor lobes 50 to isolate the chambers 24 onefrom the other.

In operation, the rotor 84 will be rotating in a clockwise directioncompressing fluid in the chambers 24 in a counterclockwise direction. Aseach rotor lobe 50 is moved into a'chamber 24 in a counterclockwisedirection, the slot 98 will open a flow path from the chamber 24 underpressure through slot 98 to discharge port 91. Simultaneously, as a lobe50 is retracted from a chamber 24, the slot 96 will providecommunication with inlet bore in the hub 16.

It should be understood that sidewall seals are provided in both thepump and engine between the side plates, rotor and idler rollers asrequired. The sidewall seals are not shown since such seals are wellknown and do not form a part of the present invention.

It should also be noted that inlet passage means and exhaust passagemeans can be provided in the housing for admitting a combustible mixtureinto the chambers or for exhausting gases from the chambers.

I claim:

1. A rotary piston device comprising a housing having a number ofchambers,

a rotor having a number of lobes equal to one less than the number ofchambers and a shaft journalled for rotation on the axis of the housing,

a series of gear teeth on the surface of each of said lobes,

a hub eccentrically mounted on the shaft, said rotor being mounted forrotation on said hub in the opposite direction of rotation of said shaftto volumetrically displace fluid in said chambers,

rotary seal members mounted in said housing between said chambers in aposition to engage the surface of the lobes on said rotor,

and a series of gear teeth on the surface of said rotary seal membersfor sealingly engaging said gear teeth on said lobes.

2. The device according to claim 1 including ignition means in each ofsaid chambers whereby said device operates as an engine.

3. The device according to claim 1 wherein said hub includes firstpassage means for admitting fluid through said shaft to said chambersand second passage means for discharging fluid from said chambersto'said shaft, said rotor including a passage between each pair oflobes, said passages being located in a common plane to providecommunication between said chambers and said first and second passagesin said hub.

4. The device according to claim 2 including inlet and exhaust ports ineach lobe and one pair of diametrically oppositely located lobes of saidrotor connected to the chambers, and wherein said hub includes a firstpassage providing communication for a combustible fuel mixture from saidshaft to said inlet port,

and a second passage providing communication for exhaust gases from saidexhaust port to said shaft.

5. The device according to claim 1 including seal means between saidhousing and said idler roller.

6. The device according to claim 5 wherein said seal means includes abrush positioned in said housing to bear against said roller for eachidler roller and a means for biasing said brush against said roller.

7. A rotary piston pump comprising a housing having a number ofchambers,

a drive shaft journalled for rotation in said housing,

a rotor having a number of lobes equal to one less than the number ofchambers in said housing eccentrically mounted on said shaft,

passage means for admitting fluid to said chambers,

passage means for allowing fluid under pressure to discharge from saidchambers,

means for rotating said drive shaft to drive said rotor in the oppositedirection of rotation from said shaft, said rotor volumetricallydisplacing any fluid in said chambers,

roller means for sealingly engaging the surface of the rotor to isolatesaid chambers one from the other,

said roller means including a number of gear teeth on its outer surfaceand said rotor including a number of gear teeth on its outer surface tointermesh with the gear teeth on the roller surface,

a pair of brushes positioned in said housing in a position to engagesaid roller means and spring means for biasing said brushes intoengagement with said roller means to seal the space between said rollermeans and said housing.

8. A rotary piston engine comprising:

a housing having a number of chambers,

ignition means in each of said chambers,

a drive shaft journalled for rotation in said housing,

a rotor having a number of lobes equal to one less than the number ofchambers, said rotor being mounted on said shaft,

inlet passage means for admitting a combustible mixture into saidchambers,

exhaust passage means connected to each of said chambers,

and a roller assembly between adjacent chambers to sealingly engage thesurface of said rotor, said rol' ler assemblies each including an idlerroller having a series of gear teeth on the outer surface and said rotorincludes a series of gear teeth positioned to intermesh with said teethon said rollers.

1. A rotary piston device comprising a housing having a number ofchambers, a rotor having a number of lobes equal to one less than thenumber of chambers and a shaft journalled for rotation on the axis ofthe housing, a series of gear teeth on the surface of each of saidlobes, a hub eccentrically mounted on the shaft, said rotor beingmounted for rotation on said hub in the opposite direction of rotationof said shaft to volumetrically displace fluid in said chambers, rotaryseal members mounted in said housing between said chambers in a positionto engage the surface of the lobes on said rotor, and a series of gearteeth on the surface of said rotary seal members for sealingly engagingsaid gear teeth on said lobes.
 2. The device according to claim 1including ignition means in each of said chambers whereby said deviceoperates as an engine.
 3. The device according to claim 1 wherein saidhub includes first passage means for admitting fluid through said shaftto said chambers and second passage means for discharging fluid fromsaid chambers to said shaft, said rotor including a passage between eachpair of lobes, said passages being located in a common plane to providecommunication between said chambers and said first and second passagesin said hub.
 4. The device according to claim 2 including inlet andexhaust ports in each lobe and one pair of diametrically oppositelylocated lobes of said rotor connected to the chambers, and wherein saidhub includes a first passage providing communication for a combustiblefuel mixture from said shaft to said inlet port, and a second passageproviding communication for exhaust gases from said exhaust port to saidshaft.
 5. The device according to claim 1 including seal means betweensaid housing and said idler roller.
 6. The device according to claim 5wherein said seal means includes a brush positioned in said housing tobear against said roller for each idler roller and a means for biasingsaid brush against said roller.
 7. A rotary piston pump comprising ahousing having a number of chambers, a drive shaft journalled forrotation in said housing, a rotor having a number of lobes equal to oneless than the number of chambers in said housing eccentrically mountedon said shaft, passage means for admitting fluid to said chambers,passage means for allowing fluid under pressure to discharge from saidchambers, means for rotating said drive shaft to drive said rotor in theopposite direction of rotation from said shaft, said rotorvolumetrically displacing any fluid in said chambers, roller means forsealingly engaging the surface of the rotor to isolate said chambers onefrom the other, said roller means including a number of gear teeth onits outer surface and said rotor including a number of gear teeth on itsouter surface to intermesh with the gear teeth on the roller surface, apair of brushes positioned in said housing in a position to engage saidroller means and spring means for biasing said brushes into engagementwith said roller means to seal the space between said roller means andsaid housing.
 8. A rotary piston engine comprising: a housing having anumber of chambers, ignition means in each of said chambers, a driveshaft journalled for rotation in said housing, a rotor having a numberof lobes equal to one less than the number of chambers, said rotor beingmounted on said shaft, inlet passage means for admitting a combustiblemixture into said chambers, exhaust passage means connected to each ofsaid chambers, and a roller assembly between adjacent chambers tosealingly engage the surface of said rotor, said roller assemblies eachincluding an idler roller having a series of gear teeth on the outersurface and said rotor includes a series of gear teeth positioned tointermesh with said teeth on said rollers.